The plumbing still is not setup right. Once the flow was unrestricted I noticed that the AGA Megaflow durso standpipe would start siphoning and lower the wier level until it got enough air. So I drilled a few more holes in the top of the standpipe. This eliminated the siphoning but is a bit noisier. I put a piece of tape over one hole as I found that two were enough to prevent the siphon. That reduced the extra noise slightly. But it is still noiser than originally and sometimes has a slight wistle. I may try gluing a little piece of small diameter tubing on the new holes like the original hole has to see if that helps.
